It is well known that potassium is an essential element for the normal functioning of the human organism. When diuretics are administered, an unacceptable reduction of serum potassium, i.e., less than 3.5 mmole/l, called hypokalemia, may result. Hypokalemia is treated by supplementing dietary potassium through various means. Potassium can be supplemented intravenously. The preferred source of potassium for this treatment is potassium chloride, because of its low cost. However, when potassium Chloride is taken orally, it can cause severe upper gastrointestinal symptoms. Additionally, potassium chloride has a bitter taste.
To avoid these disadvantages in oral applications, potassium chloride is used in an enteric-coated form. This approach, however, also has its disadvantages. Recent observations suggest that the dissolution of the enteric coating in the small intestine and the resulting high local concentration of potassium on the mucosa may produce ulceration, obstruction, or bleeding.
For this reason, organic potassium salts, which are more palatable and can be given without an enteric coating (and without untoward local effects on the intestine), have come into widespread use. Potassium gluconate and potassium "triplex" (citrate, acetate and bicarbonate) are the most frequently employed. The above organic potassium salts, however, have several disadvantages. Potassium gluconate delivers less than half the weight of potassium per weight of dosage than does potassium chloride, requiring larger doses of the compound. The potassium acetate used in "triplex" is a diuretic, which can exacerbate the potassium deficiency of the patient, and is also deliquesent, which makes storage and handling of the salt difficult. Additionally, the "triplex" compounds are all water soluble, which indicates that the potassium ion, which is bitter tasting, is released in the mouth.
The present invention provides a method of treating hypokalemia that overcomes the disadvantages of the above potassium sources. Kurrol's salt, also known as potassium polyphosphate or potassium metaphosphate, delivers potassium in a pleasant-tasting form that is easily handled and delivered. The salt diassociates in the stomach, not the mouth, releasing potassium ions where they can be easily assimilated. The polyphosphate is not only nonirritating, but also degrades through hydrolysis in the stomach to act as a buffer.
Phosphates as Food Ingredients, R. H. Ellinger, CRC press, 1972, discloses that calcium, iron, sodium and potassium phosphates are used to improve the nutritional properties of numerous cereal products. Kurrol's salt is presently used as a food ingredient for such uses as a meat preservative, a fungi or yeast inhibitor, or a tenderizer for the skins of fruits and vegetables. The above reference, however, fails to disclose the use of Kurrol's salt as a potassium-containing nutritional supplement to treat hypokalemia, particularly as a supplement that overcomes the disadvantages of the supplements discussed above. Additionally, the amounts of Kurrol's salt used in the above applications is typically less than 0.5 weight % of the food treated, resulting in insufficient amounts of Kurrol's salt being ingested in the normal diet to be effective to treat hypokalemia.